14,254 research outputs found
Clinical Evaluation of the Osteointegration
INTRODUCTION: The treatment of the complete or partially edentulous patient with a prothesis supported by dental implants is a procedure with high predictability. Themost important factor is the osteointegration of the implant.
AIM OF PRESENTATION: Analysis of the clinical methods of evaluation of the osteointegration.
DESCRIPTION: The method most commonly used is the intraoral radiograph that allows us to study the level of the bone and to identify radiolucencies around the implant. This technique will be modified by the quality of the X-ray image, the range of the optical system of humans, subjective interpretation and the problem of quantifying. The X-ray is not enough. Digital X-ray systems provide some advantages such us lower exposure to radiation, the possibility of modifying images, measuring lengths and angles, and densitometric studies. The resonance frequency analysis syste(Osstell) is a technique that evaluates the stability of the interface bone-implant. Used when connecting the abutments, it shows us the degree of osteointegration (protocols of early loading)
L1CAM binds ErbB receptors through Ig-like domains coupling cell adhesion and neuregulin signalling.
During nervous system development different cell-to-cell communication mechanisms operate in parallel guiding migrating neurons and growing axons to generate complex arrays of neural circuits. How such a system works in coordination is not well understood. Cross-regulatory interactions between different signalling pathways and redundancy between them can increase precision and fidelity of guidance systems. Immunoglobulin superfamily proteins of the NCAM and L1 families couple specific substrate recognition and cell adhesion with the activation of receptor tyrosine kinases. Thus it has been shown that L1CAM-mediated cell adhesion promotes the activation of the EGFR (erbB1) from Drosophila to humans. Here we explore the specificity of the molecular interaction between L1CAM and the erbB receptor family. We show that L1CAM binds physically erbB receptors in both heterologous systems and the mammalian developing brain. Different Ig-like domains located in the extracellular part of L1CAM can support this interaction. Interestingly, binding of L1CAM to erbB enhances its response to neuregulins. During development this may synergize with the activation of erbB receptors through L1CAM homophilic interactions, conferring diffusible neuregulins specificity for cells or axons that interact with the substrate through L1CAM
Coastal vulnerability in the Mediterranean sector between Fnideq and M’diq (North of Morocco)
This study assessed coastal vulnerability to erosion processes along a 24-
km-long littoral with different levels of human occupation. An aerial photogram-
metric flight and a Quickbird satellite image were used for mapping land uses
and reconstructing coastal evolution from 1986 to 2003. Maximum erosion (-
2.48 myr−1) was recorded south of Marina Kabila port and maximum accretion
(+2.25 myr−1) south of Marina Smir port. Erosion/accretion rates have been
divided into five categories and land uses have been mapped and divided into
three categories. Coastal vulnerability has been assessed by combining coastal
trend with land-use categories: 10% of the littoral recorded “very high” vulner-
ability, 29% recorded “high” vulnerability, and 61% of the investigated littoral
presented “null” and “low” vulnerability. The “Imminent Collapse Zone”, i.e.
the littoral zone threatened by imminent erosion, presented mean values of 10.34
m, with maximum and minimum values of 15.3 and 7.6 m, respectively. Several
human structures and activities are located within the imminent collapse zone
and consequently will be threatened by severe erosion in near future
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Comparison of Interactions Between Control and Mutant Macrophages
This paper presents a preliminary study on macrophages migration in Drosophila embryos, comparing two types of cells. The study is carried out by a framework called macrosight which analyses the movement and interaction of migrating macrophages. The framework incorporates a segmentation and tracking algorithm into analysing motion characteristics of cells after contact. In this particular study, the interactions between cells is characterised in the case of control embryos and Shot3 mutants, where the cells have been altered to suppress a specific protein, looking to understand what drives the movement. Statistical significance between control and mutant cells was found when comparing the direction of motion after contact in specific conditions. Such discoveries provide insights for future developments in combining biological experiments to computational analysis
Evaluation and Correction of B1+-Based Brain Subject-Specific SAR Maps Using Electrical Properties Tomography
The specific absorption rate (SAR) estimates the amount of power absorbed by the tissue and is determined by the electrical conductivity and the E-field. Conductivity can be estimated using Electric Properties Tomography (EPT) but only the E-field component associated with B-1(+) can be deduced from B-1- mapping. Herein, a correction factor was calculated to compensate for the differences between the actual SAR and the one obtained with B-1(+). Numerical simulations were performed for 27 head mod-els at 128 MHz. Ground-truth local-SAR and 10g-SAR (SAR(GT)) were computed using the exact electrical conductivity and the E-field. Estimated local-SAR and 10g-SAR (SAR(EST)) were com-puted using the electrical conductivity obtained with a convection-reaction EPT and the E-field obtained from B-1(+). Correction factors (CFs) were estimated for gray matter, white matter, and cere-brospinal fluid (CSF). A comparison was performed for different levels of signal-to-noise ratios (SNR). Local-SAR/10g-SAR CF was 3.08 +/- 0/06 / 2.11 +/- 0.04 for gray matter, 1.79 +/- 0/05 / 2.06 +/- 0.04 for white matter, and 2.59 +/- 0/05 / 1.95 +/- 0.03 for CSF. SAR(EST) without CF were underestimated (ratio across [infinity -25] SNRs: 0.52 +/- 0.02 for local-SAR; 0.55 +/- 0.01 for 10g-SAR). After cor-rection, SAREST was equivalent to SAR(GT) (ratio across [infinity -25] SNRs: 0.97 +/- 0.02 for local-SAR; 1.06 +/- 0.01 for 10g-SAR). SAR maps based on B-1(+) can be corrected with a correction factor to compensate for potential differences between the actual SAR and the SAR calculated with the E-field derived from B-1(+)
Analyzing the Impact of Roadmap and Vehicle Features on Electric Vehicles Energy Consumption
Electric Vehicles (EVs) market penetration rate is continuously increasing due to several aspects such as pollution reduction initiatives, government incentives, cost reduction, and fuel cost increase, among others. In the vehicular field, researchers frequently use simulators to validate their proposals before implementing them in real world, while reducing costs and time. In this work, we use our ns-3 network simulator enhanced version to demonstrate the influence of the map layout and the vehicle features on the EVs consumption. In particular, we analyze the estimated consumption of EVs simulating two different scenarios: (i) a segment of the E313 highway, located in the north of Antwerp, Belgium and (ii) the downtown of the city of Antwerp with real vehicle models. According to the results obtained, we demonstrate that the mass of the vehicle is a key factor for energy consumption in urban scenarios, while in contrast, the Air Drag Coefficient (C-d) and the Front Surface Area (FSA) play a critical role in highway environments. The most popular and powerful simulations tools do no present combined features for mobility, realistic map-layouts and electric vehicles consumption. As ns-3 is one of the most used open source based simulators in research, we have enhanced it with a realistic energy consumption feature for electric vehicles, while maintaining its original design and structure, as well as its coding style guides. Our approach allows researchers to perform comprehensive studies including EVs mobility, energy consumption, and communications, while adding a negligible overhead
Mitigating Electromagnetic Noise When Using Low-Cost Devices in Industry 4.0
Transitioning toward Industry 4.0 requires major investment in devices and mechanisms enabling interconnectivity between people, machines, and processes. In this article, we present a low-cost system based on the Raspberry Pi platform to measure the overall equipment effectiveness (OEE) in real time, and we propose two filtering mechanisms for electromagnetic interferences (EMIs) to measure OEE accurately. The first EMI filtering mechanism is the database filter (DBF), which has been designed to record sealing signals accurately. The DBF works on the database by filtering erroneous signals that have been inserted in it. The second mechanism is the smart coded filter (SCF), which is used to filter erroneous signals associated with machine availability measurements. We have validated our proposal in several production lines in a food industry. The results show that our system works properly, and that it considerably reduces implementation costs compared with proprietary systems offering similar functions. After implementing the proposed system in actual industrial settings, the results show a mean error (ME) of -0.43% and a root mean square error (RMSE) of 4.85 in the sealing signals, and an error of 0% in the availability signal, thus enabling an accurate estimate of OEE
Fat-to-glucose interconversion by hydrodynamic transfer of two glyoxylate cycle enzyme genes
The glyoxylate cycle, which is well characterized in higher plants and some microorganisms but not in vertebrates, is able to bypass the citric acid cycle to achieve fat-to-carbohydrate interconversion. In this context, the hydrodynamic transfer of two glyoxylate cycle enzymes, such as isocytrate lyase (ICL) and malate synthase (MS), could accomplish the shift of using fat for the synthesis of glucose. Therefore, 20 mice weighing 23.37 ± 0.96 g were hydrodinamically gene transferred by administering into the tail vein a bolus with ICL and MS. After 36 hours, body weight, plasma glucose, respiratory quotient and energy expenditure were measured. The respiratory quotient was increased by gene transfer, which suggests that a higher carbohydrate/lipid ratio is oxidized in such animals. This application could help, if adequate protocols are designed, to induce fat utilization for glucose synthesis, which might be eventually useful to reduce body fat depots in situations of obesity and diabetes
Mkp3 is a negative feedback modulator of Fgf8 signaling in the mammalian isthmic organizer
The pivotal mechanisms that govern the correct patterning and regionalization of the distinct areas of the mammalian CNS are driven by key molecules that emanate from the so-called secondary organizers at neural plate and tube stages. FGF8 is the candidate morphogenetic molecule to pattern the mesencephalon and rhombencephalon in the isthmic organizer (IsO). Recognizable relevance has been given to the intracellular pathways by which Fgf8 is regulated and modulated. In chick limb bud development, a dual mitogen-activated protein kinase phosphatase-3 (Mkp3) plays a role as a negative feedback modulator of Fgf8 signaling. We have investigated the role of Mkp3 and its functional relationship with the Fgf8 signaling pathway in the mouse IsO using gene transfer microelectroporation assays and protein-soaked bead experiments. Here, we demonstrate that MKP3 has a negative feedback action on the MAPK/ERK-mediated FGF8 pathway in the mouse neuroepithelium. (C) 2004 Elsevier Inc. All rights reserved.info:eu-repo/semantics/publishedVersio
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